Skip to main content

XML Validation using XSD schema

We are going to validate XML using XSD schema in Java. We will create XML Schema using XSD and then use same schema to create the XML file. Then we will write our code to validate this XML against same schema.

XSD Schema creation

Below is our schema where we are defining the Schema for XML elements. In this schema we creating two elements, one for request and another for response. We are publishing this schema using targetNamespace which we will use during XML creation.
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           xmlns:tns="http://services.ttj.com/hello-service"
           targetNamespace="http://services.ttj.com/hello-service" elementFormDefault="qualified">

    <xs:element name="sayHelloRequest">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="userName" type="xs:string"/>
            </xs:sequence>
        </xs:complexType>
    </xs:element>

    <xs:element name="sayHelloResponse">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="message" type="xs:string"/>
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>

XML creation using schema

In below XML we are using the above schema to create the request element. In below XML we are using the XSD schema which we published using targetNamspace and same namespace we will use here.
<sayHelloRequest xmlns="http://services.ttj.com/hello-service">
     <userName>Black smith</userName>
</sayHelloRequest>

Validating XML against schema

Below is our code where we are using Java API to validate the XML request using XSD schema.
import javax.xml.XMLConstants;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import java.io.File;

public class ValidateXmlMain {
    public static void main(String[] args){
        String xsdSchemaLoc = "/Users/ttj/My_blogs_workspace/resources/hello-service-schema.xsd";
        String xmlFileLoc = "/Users/ttj/My_blogs_workspace/resources/hello-service-request.xml";

        try {
            SchemaFactory factory =
                    SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
            Schema schema = factory.newSchema(new File(xsdSchemaLoc));
            Validator validator = schema.newValidator();
            validator.validate(new StreamSource(new File(xmlFileLoc)));
            System.out.println("Validated successfully.");
        }catch(Exception e){
            System.out.println("Validation failed...");
            e.printStackTrace();
        }
    }

}

Validate XML request with schema namespace

Now if we run this code it will validate the XML successfully and will print below result.
Validated successfully.
If you remove the XML namespace from XML request then you may get below error which you can fix by adding the namespace back to XML.
org.xml.sax.SAXParseException; systemId: file:/Users/ttj/My_blogs_workspace/resources/hello-service-request.xml; lineNumber: 1; columnNumber: 18; cvc-elt.1: Cannot find the declaration of element 'sayHelloRequest'.
 at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203)

Comments

Popular Posts

SpringBoot - @ConditionalOnProperty example for conditional bean initialization

@ConditionalOnProperty annotation is used to check if specified property available in the environment or it matches some specific value so it can control the execution of some part of code like bean creation. It may be useful in many cases for example enable/disable service if specific property is available. Below are the attributes which can be used for property check.
havingValue - Provide the value which need to check against specified property otherwise it will check that value should not be false.matchIfMissing - If true it will match the condition and execute the annotated code when property itself is not available in environment.name - Name of the property to be tested. If you want to test single property then you can directly put the property name as string like "property.name" and if you have multiple properties to test then you can put the names like {"prop.name1","prop.name2"}prefix - It can be use when you want to apply some prefix to all prop…

Asynchronous REST service implementation in Spring boot

In this tutorial we will see how to create an asynchronous REST service endpoint using Spring boot application.
Asynchronous service works in a way that it will not block the client request and do the processing in separate thread. When work is complete the response returned to the client so our service will be able to handle more client requests at the same time, compare to synchronous processing model.
Let's understand how it is working in synchronous mode. In such server/client application at server side it has a pool of threads which are serving the request. If a request received by a thread then it will be blocked until it send the response back to client. In this case if processing doesn't take much time it will be able to process it quickly and accept other client requests but there could be one situation when all threads are busy and not able to accept the new client requests.

To overcome of such problems, asynchronous processing model introduced for REST services. In…

Entity to DTO conversion in Java using Jackson

It's very common to have the DTO class for a given entity in any application. When persisting data, we use entity objects and when we need to provide the data to end user/application we use DTO class. Due to this we may need to have similar properties on DTO class as we have in our Entity class and to share the data we populate DTO objects using entity objects. To do this we may need to call getter on entity and then setter on DTO for the same data which increases number of code line. Also if number of DTOs are high then we need to write lot of code to just get and set the values or vice-versa.
To overcome this problem we are going to use Jackson API and will see how to do it with minimal code only.
Maven dependency <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.9.9</version> </dependency> Entity class Below is our ent…

Setting up kerberos in Mac OS X

Kerberos in MAC OS X Kerberos authentication allows the computers in same domain network to authenticate certain services with prompting the user for credentials. MAC OS X comes with Heimdal Kerberos which is an alternate implementation of the kerberos and uses LDAP as identity management database.
Here we are going to learn how to setup a kerberos on MAC OS X which we will configure latter in our application.
Installing Kerberos In MAC we can use Homebrew for installing any software package. Homebrew makes it very easy to install the kerberos by just executing a simple command as given below.
brew install krb5 Once installation is complete, we need to set the below export commands in user's profile which will make the kerberos utility commands and compiler available to execute from anywhere.
Open user's bash profile:
vi ~/.bash_profile Add below lines:
export PATH=/usr/local/opt/krb5/bin:$PATH export PATH=/usr/local/opt/krb5/sbin:$PATH export LDFLAGS="-L/usr/lo…